On the Analogy between Strong Interaction and Electromagnetic Interaction

According to Sakata's composite hypothesis of heavy particles, we assume that the fundamental particles do not change their kind through strong interactions. A formulation of these interactions is given by requiring the invariance under the gauge transformation of the first kind applied to each baryon field. If we assume that the phase function depends on the space-time coordinate, it leads to the existence of a neutral vector meson analogous to the electromagnetic field the mass of which need not always vanish. Its consequences are examined and found to be quite favourable for the interpretation of the strong interaction. In particular, it leads to the conserevation law of parity in strong interactions and the condition for the existence of the composite state.